This invention relates to a rotor for a centrifuge, wherein said rotor is rotatably driven about a rotation axis and consists of two parts, i.e. a central bearing part and a waste collecting part which is provided with a waste collecting area, the waste collecting part is separable from the bearing part for waste disposal or cleaning, the bearing part and the waste collecting part are provided with torque transmitting means which interact with each other in a form-fitting and/or adherence manner and are connectable by axially positioning the waste collecting part on the bearing part and disconnectable by axially removing the waste collecting part from the bearing part. The invention moreover relates to a centrifuge.
Centrifuges have been used for decades for a variety of applications and are thus known from practice in many different designs. A rotor with the above specified features is described in the Assignee's older, not prior published German utility model application no. 20 2004 004 215.0. In the rotor described therein, the bearing part comprises one recoil nozzle or a plurality of recoil nozzles for driving the rotor by means of lubricating oil exiting via the nozzle or the nozzles so that the bearing part here forms a drive part of the rotor.
With all centrifuges known and used so far, an inside diameter of the rotor is generally centered on an outside diameter of the axis or an outside diameter of a component located between axis and rotor, such as rotor bearing or drive part. To be able to assemble and disassemble a two-part rotor consisting of a bearing part and a waste collecting part, an assembly clearance between the parts of the rotor is required as a rule; at maximum, slight pressing is permissible so that the rotor can still be assembled and disassembled. To save weight and manufacturing costs, it is increasingly aimed at building the rotor as light-weight as possible, for example by using plastic instead of metal. During operation of the centrifuge, a waste collecting part of plastic is subject in particular to the risk of deformation under the effect of centrifugal forces and/or heat. In the rotors known so far, this results in the inside diameter of the waste collecting part becoming larger. Thus, in centrifuge operation, an increasing clearance results in the area of the connection between waste collecting part and bearing part, resulting in an increasing imbalance and thus performance losses of the centrifuge, a reduced bearing life, and in offending noises.
Accordingly, it is the objective of this invention to provide a rotor and a centrifuge of the type indicated in the beginning which avoid the disadvantages indicated and, in particular, the occurrence of imbalances in operation, thus ensuring high performance with a good endurance limit and a low operating noise level.